Image sensors utilize analog-to-digital converters (ADCs) to convert the analog pixel signal into a digital signal prior to signal processing. In conventional column readout architectures, each column of the pixel array has a dedicated readout circuit and corresponding ADC. The readout circuit typically includes a sample and hold circuit using a capacitor and a buffer, where the pixel signal is sampled prior to being converted into a digital signal. The maximum voltage for the readout signal may be high (e.g., 3.3V) due to the pixel output swing. As such, the input swing for the ADC must match that of the pixel output swing. Conventional circuits utilize amplifiers to increase the pixel output swing. Matching the high voltage results in the ADC operating at a higher voltage and therefore requires more power, which generally adds to the cost of the device. Other readout circuits have been designed to attenuate the signal, however, signal attenuation results in the loss of information, which introduces bit errors when the signal is converted to a digital signal.